Fig. 4: Forward propagating waves in EL central processes.
From: Closed-loop two-photon functional imaging in a freely moving animal
2nd instar larva expressed GCaMP8m and hexameric mCherry under EL control. During the 269 s recording shown, the larva traveled 11 mm from its original position along a path length of 13.4 mm (a) X-Y and X-Z projection of template image created from mCherry channel of labeled VNC. Colored circles indicate VOIs analyzed in (b, d, f). Each VOI consisted of two spherical regions centered on the nodules on either side of the midline. White dashed line indicates volume projected in (c, e). b Ratiometric (GCaMP8m/mCherry) measurement of activity in VOIs over the time course of the experiment, normalized separately for each VOI. The larva crawled forward for the duration of the experiment, as indicated by the teal box labeled with F. c Time-space projection of ratiometric activity measure. The vertical (space) axis spans the range from the bottom of the white box to the top. The horizontal (time) axis matches (b). The color scale is normalized so that the median of the entire data set shown in the panel is 1. (d–e) Expanded views of voi ratio (d) and projected ratios (e) during highlighted epoch. c, d use the same color scale. f Cycle-average ratiometric activity measure in each VOI vs. phase (ϕ) during forward crawling. Each VOI is normalized separately so that the minimum mean activity is 1. g Amplitude and phase of posterior-anterior wave in green fluorescence associated with each voxel in the central processes (white boxed region in (a)). The amplitude is normalized relative to the median green fluorescence of the region. 25 µm scale bar in (a, g).
